First record of autochthonous canine leishmaniasis in Hungary

Abstract

Hungary is traditionally regarded as a leishmaniasis-free country, and human or canine cases diagnosed locally have been recorded as imported. However, recent entomological surveys have verified the presence in Hungary of Phlebotomus neglectus and Phlebotomus perfiliewi perfiliewi, which have been incriminated as competent vectors of Leishmania infantum elsewhere in Europe. Following the occurrence in October 2007 of an undisputable clinical case of L. infantum canine leishmaniasis (CanL) in a 4-year-old female pug in a kennel of 20 dogs in Tolna province, an investigation was performed to assess the infection status in that canine population and to search for putative phlebotomine vectors. Another female pug became sick during the study period (May-November 2008) and L. infantum was confirmed as the causative agent. The other animals appeared clinically healthy; however, 4 additional dogs were found positive by indirect fluorescent antibody test (2 dogs), or by buffy-coat PCR (1 dog), or by both methods (1 dog). Hence the overall Leishmania infection prevalence in the kennel was 30% (6/20). All dogs were born in the same place and had been always kept outdoors. They had neither been abroad nor received a blood transfusion. No sand flies were collected with CDC Standard Miniature Light traps, Mosquito Magnet(®) X (MMX) dry ice-baited traps, or sticky traps placed either in or around the kennel and at nearby chicken yards during July and August of 2008 and 2009. Considering the dogs' historical background and the failure to trap any sand fly vectors in the kennel area, the origin of CanL in this site remains unexplained.

FIG. 1.

Location of the sites of autochthonous cases of canine leishmaniasis (○), Phlebotomus neglectus (□), and Phlebotomus perfiliewi perfiliewi (▵) in Hungary.

FIG. 2.

Spleen of the index case (dog P01). Macrophages of red pulp loaded with Leishmania amastigotes (arrows; hematoxylin and eosin stain; scale bar=12.5 μm). Color images available online at www.liebertpub.com/vbz

FIG. 3.

Liver of the index case (dog P01). Hepatic intralobular granuloma formation composed of macrophages loaded with Leishmania amastigotes (arrows), plasmacytes, and lymphocytes (hematoxylin and eosin stain; scale bar=12.5 μm). Color images available online at www.liebertpub.com/vbz

FIG. 4.

Spleen of the index case (dog P01), showing several immunolabeled Leishmania amastigotes within macrophages (inset shows spleen of a dog infected with distemper virus; no immunostaining is visible). Horseradish peroxidase-labeled polymer method (scale bar=12.5 μm). Color images available online at www.liebertpub.com/vbz

FIG. 5.

PCR amplicons resulting from kDNA PCR of 20 dogs (P01–P20). Positive samples of liver (P01L), spleen (P01S), and lymph nodes (P01N), of the index case (dog P01), and peripheral blood of the second diseased dog (P12) show the 145-bp-long fragments specific for L. infantum kDNA (indicated by the arrowhead; N, negative probe; P, positive probe).